With little warning or explanation, the Centers for Disease Control and Prevention recently canceled a major climate change conference that had been scheduled for next month in Atlanta.

The Climate and Health Summit, which had been in the works for months, was intended as a chance for public health officials around the country to learn more about the mounting evidence detailing the risks to human health posed by the changing climate. But CDC officials abruptly canceled the conference the week before President Donald Trump's inauguration, sending a terse email to those who had been scheduled to speak at the event. The message did not explain the reason behind the decision.

"Unfortunately, we are unable to hold the Summit in February 2017," CDC officials wrote, adding that the agency is "currently exploring" whether it could reschedule the event later in the year.

CDC officials contacted by The Washington Post have not commented about the cancellation, which was first reported by E&E News.

But one scheduled keynote speaker, Georges Benjamin, executive director of the American Public Health Association, said agency officials decided to pre-emptively call off the summit, rather than risk running afoul of an incoming president who has repeatedly called climate change a "hoax" and has nominated climate change skeptics to his Cabinet.

"They ran it up the flagpole and realized that it was so close to the inauguration, the chances of it being canceled were pretty real with the administration that was coming in," said Benjamin, whose organization was one of the promoters of the event. "Some might argue they should have said, 'We're going to do this and make them tell us no.' But that was the decision they made. We should think of this as a strategic retreat."

Another scheduled speaker, Edward Maibach, director of the Center for Climate Change Communication at George Mason University, argued that the summit should have gone forward, no matter who had just been sworn in as the next president. He said he fears the move will set a precedent of government officials self-silencing, in part over fears of reprisal or loss of funding, rather than standing behind the established science around climate change.

"I don't know why they canceled the meeting, but I do know the meeting was important and should have been held. Politics is politics, but protecting the health of our citizens is one of our government's most important obligations to us," Maibach said in an email. "Climate change is bad for America, and bad for the world, in so many ways. One of these ways is that it is harming our health, already, and is likely to get much worse over the next few decades unless we take action. As the nation's public health agency, we need CDC to be fully engaged in protecting our health from climate change."

Evidence has continued to mount that climate change could pose major health risks to people around the world over the course of the 21st century.

A report published in the Lancet last year, which included 45 authors in Europe and China, found that aggressively tackling the problem of climate change could be "the greatest global health opportunity of this century," but that not addressing the problem "threatens to undermine the last half century of gains in development and global health."

The Obama administration also viewed the problem as a serious threat, and the White House last year held its own summit on climate change and public health. The Obama White House also undertook multiple initiatives to highlight the links between climate and health, most recently issuing a 300-page report last summer that underscored how a warming climate could exacerbate major public health problems.

Among the threats: Millions more deaths caused by extreme heat. More frequent outbreaks of diseases transmitted by ticks and mosquitoes. Longer allergy seasons. Worsening air quality that could result in thousands more premature deaths each year from respiratory problems.

Benjamin said Monday that he hopes the CDC is able to reschedule the summit, as it mentioned in its email. But even if it doesn't, he said his organization and other nongovernment groups will continue to spotlight the ominous connections between the planet's changing climate and threats to human health.

"We're committed to making sure the nation knows about the effects of climate change on health," he said. "If anyone doesn't think this severe problem, they are fooling themselves."